Realization spaces of 4-polytopes are universal

Let $P\subset\R^d$ be a $d$-dimensional polytope. The {\em realization space} of~$P$ is the space of all polytopes $P'\subset\R^d$ that are combinatorially equivalent to~$P$, modulo affine transformations. We report on work by the first author, which shows that realization spaces of \mbox{4-dimensional} polytopes can be ``arbitrarily bad'': namely, for every primary semialgebraic set~$V$ defined over~$\Z$, there is a $4$-polytope $P(V)$ whose realization space is ``stably equivalent'' to~$V$. This implies that the realization space of a $4$-polytope can have the homotopy type of an arbitrary finite simplicial complex, and that all algebraic numbers are needed to realize all $4$- polytopes. The proof is constructive. These results sharply contrast the $3$-dimensional case, where realization spaces are contractible and all polytopes are realizable with integral coordinates (Steinitz's Theorem). No similar universality result was previously known in any fixed dimension.Comment: 10 page

Prearranged glycosides part 16. Non-symmetrically tethered glycosides via o-Hydroxycarbonyl-benzylidene-glycosides

An asymmetric o-methylbenzoyl tether for intramolecular glycosylations is prepared from o-methoxycarbonyl-benzylidene glucosamine by benzylation, saponification, condensation with phenyl 3,4,6-benzyl-1-thio-glucoside, and regioselective ring opening of the benzylidene moiety. Thus obtained prearranged glycoside affords the corresponding beta(1,4)-linked disaccharide as the major product

Rabbit Anti T-Lymphocyte Globulin Induces Apoptosis in Peripheral Blood Mononuclear Cell Compartments and Leukemia Cells, While Hematopoetic Stem Cells Are Apoptosis Resistant

AbstractPolyclonal anti-T-lymphocyte globulins (ATG) are used in allogeneic stem cell transplantation (SCT) for the prophylaxis of graft versus host disease (GVHD) by in vivo T cell depletion. In this study we investigated the complement independent induction of apoptosis by rabbit ATG in peripheral blood mononuclear cell (PBMNC) compartments and hematopoetic stem cells (HSC). We also detected antileukemic activity of ATG by measuring apoptosis in myeloid and lymphatic leukemia cell lines and primary leukemia cells. We found ATG to induce apoptosis in T-lymphocytes (CD4+, CD8+), B-lymphocytes (CD20+), natural killer (NK)-cells (CD56+), and monocytes (CD14+). HSC, in contrast, were apoptosis resistant and could be growth stimulated by low-dose ATG in the presence of bystander cells. The human leukemia cell lines Jurkat, Daudi, DG-75 (lymphoblastic), and K562, HL-60, KG1, and U937 (myeloblastic) underwent ATG-induced apoptosis, whereas the NK-cell line YT was resistant. Primary leukemia cells from 6 investigated patients with acute lymphoblastic leukemia, 9 of 10 patients with chronic lymphocytic leukemia, and 4 of 8 patients with acute myeloblastic leukemia underwent ATG-induced apoptosis. We conclude apoptosis induction in all PBMNC compartments contributes to GVHD prophylaxis. ATG might support engraftment. Finally, antileukemic activity of ATG could positively influence the transplantation outcome

HCI engineering: charting the way towards methods and tools for advanced interactive systems

This workshop intends to establish the basis of a roadmap addressing engineering challenges and emerging themes in HCI. Novel forms of interaction and new application domains involve aspects that are currently not sufficiently covered by existing methods and tools. The workshop will serve as a venue to bring together researchers and practitioners interested the Engineering of Human- Computer Interaction and in contributing to the definition of a roadmap for the field. The intention is to continue work on the roadmap in follow-up workshops as well as in the IFIP Working Group on User Interface Engineering.(undefined)info:eu-repo/semantics/publishedVersio

Photoelektrosynthese von Wasserstoff mit Silizium-Dünnschicht-Tandemsolarzellen

In dieser Arbeit werden Photoelektroden auf Basis von Tandemsolarzellen aus Dünnschichtsilizium für die Wasserspaltung untersucht. Die Photoelektroden werden als photoaktive Kathoden für die Wasserstoffentwicklungsreaktion in einer photoelektrochemischen Zelle eingesetzt. Die Solarzellen bestehen aus zwei p-i-n-Dioden aus amorphen und mikrokristallinen Silizium in Superstrat-Geomerty. Der Rückkontakt dieser Zellen ist in Kontakt zum Elektrolyt und fungiert als Schutzschicht, um die Korrosion der Halbleiterstruktur durch den Elektrolyten zu verhindern. Als Rückkontakt werden metallisches Silber und oxdische Schutzschichten aus Titan-, Nickel-, Zinnoxid untersucht. Zur Herabsetzung von Überspannungsverlusten während der Wasserstoffentwicklung werden Katalysatoren aufgebracht. Zur Aufklärung der chemischen und elektronischen Eigenschaften der Grenzflächen wird Photoelektronenspektroskopie eingesetzt. Die Charakterisierung der Photoelektroden erfolgt über verschiedene elektrochemische Methoden. Die Photoelektroden (a-Si:H/a-Si:H) mit einer RuO2-Gegenelektrode ermöglichen die Spaltung von Wasser ohne eine externe Stromquelle. Unter simuliertem Sonnenlicht wird unter Kurzschlussbedingungen eine Licht-zu-Wasserstoff-Effizienz von 5,5 % erreicht. Durch Aufbringung einer Schutzschicht aus Titanoxid kann die Stabilität der Photoelektroden deutlich gesteigert werden. Allerdings ist eine Reduzierung in der Photospannung zu beobachten, die durch Ausbildung einer Siliziumoxid-Grenzschicht hervorgerufen wird. Durch Anpassung der Abscheidebedingungen lässt sich dieser Verlust jedoch minimieren. Photoelektroden mit Nickeloxid sind ebenfalls stabil und zeigen auch ohne Edelmetall-Katalysator eine hohe Effizienz. Die Optimierung wird in dieser Arbeit durch die systematische Aufklärung der an der Photoelektrode beteiligten Grenzflächen ermöglicht und es wird ein grundlegendes Verständnis der Charakteristik einer Photoelektroden entwickelt

Downregulation of Tumor Necrosis Factor Expression in the Human Mono-Mac-6 Cell Line

Mono-Mac-6 cells, but not U937 cells, can be Induced to rapidly express tumor necrosis factor (TNF) mRNA and protein when triggered with Ilpopolysaccharlde (LPS) at 1 pg/mI. Preincubatlon of the cells for 3 d with low amounts of LPS (10 ng/mI) results In nearly complete suppression of TNF secretion. This downreguiatlon appears to occur at the pretranslational level since specIfIc mRNA is virtually undetectable under these conditions. By contrast, the same prelncubatlon with 10 ng/mI LPS results in enhanced phagocytosls (28.6-67.2% for Staphylococcus aureus), demonstrating that not all monocyte functions are suppressed. While these results show that only stringent exclusion of LPS from culture media allows for Induction of TNF In the Mono-Mac-6 cell line, the pronounced effect of LPS preincubatlon may also provide a suitable model with which to study the mechanisms of LPS-lnduced desensitizatIon

Welcome to EICS 2015

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A Parallel Mesh-Adaptive Framework for Hyperbolic Conservation Laws

We report on the development of a computational framework for the parallel, mesh-adaptive solution of systems of hyperbolic conservation laws like the time-dependent Euler equations in compressible gas dynamics or Magneto-Hydrodynamics (MHD) and similar models in plasma physics. Local mesh refinement is realized by the recursive bisection of grid blocks along each spatial dimension, implemented numerical schemes include standard finite-differences as well as shock-capturing central schemes, both in connection with Runge-Kutta type integrators. Parallel execution is achieved through a configurable hybrid of POSIX-multi-threading and MPI-distribution with dynamic load balancing. One- two- and three-dimensional test computations for the Euler equations have been carried out and show good parallel scaling behavior. The Racoon framework is currently used to study the formation of singularities in plasmas and fluids.Comment: late submissio

How to Match Tracks of Visual Features for Automotive Long-Term SLAM

Accurate localization is a vital prerequisite for future assistance or autonomous driving functions in intelligent vehicles. To achieve the required localization accuracy and availability, long-term visual SLAM algorithms like LLama-SLAM are a promising option. In such algorithms visual feature tracks, i.e. landmark observations over several consecutive image frames, have to be matched to feature tracks recorded days, weeks or months earlier. This leads to a more challenging matching problem than in short-term visual localization and known descriptor matching methods cannot be applied directly. In this paper, we devise several approaches to compare and match feature tracks and evaluate their performance on a long-term data set. With the proposed descriptor combination and masking ("CoMa") method the best track matching performance is achieved with minor computational cost. This method creates a single combined descriptor for each feature track and furthermore increases the robustness by capturing the appearance variations of this track in a descriptor mask

BRAFV600E mutations in malignant melanoma are associated with increased expressions of BAALC

<p>Abstract</p> <p>Bachground</p> <p>Activating <it>BRAF </it>mutations are present in approximately 50% of melanomas. Although different downstream target genes of the most common mutant V600E have been identified, the contribution of activating <it>BRAF </it>mutations to malignant transformation needs further clarification.</p> <p>Methods</p> <p>Microarray gene analysis was performed for human melanoma cell lines harboring BRAF^V600Emutations in comparison to cell lines without this mutation.</p> <p>Results</p> <p>This analysis revealed a more than two fold down-regulation of 43 and an increase of 39 gene products. <it>BAALC </it>(<it>Brain and acute Leukaemia, cytoplasmatic</it>) was most prominently regulated, since it was up-regulated in mutated cell lines by a mean of 11.45. Real time PCR analyses with RNA from melanoma cell lines (n = 30) confirmed the <it>BRAF</it>-activation dependent up-regulation of <it>BAALC</it>.</p> <p>Conclusion</p> <p><it>BAALC</it>, which has been associated with cell dedifferentiation and migration, may function as a downstream effector of activating <it>BRAF </it>mutations during melanomagenesis.</p